Optical pointing device including power supply voltage drop portion and power supply voltage boost portion, and power supply semiconductor device therefor

Abstract

An optical pointing device and a power supply semiconductor device therefore are provided. The optical pointing device includes at least one power supply voltage drop portion, wherein each of the power supply voltage drop portion comprises: a voltage-drop regulator for outputting a dropped power supply voltage; a first reference voltage generator for generating a first reference voltage; a first voltage division controller for outputting first and second drop voltage division control signals according to the moving velocity; a first voltage divider for outputting a first varied division voltage in response to the first and second drop voltage division control signals; a first comparator for comparing the level of the first varied division voltage with the level of the first reference voltage to output a first comparison output signal; and a first switch controller for dropping the output voltage of the voltage-drop regulator in response to the first comparison output signal.

Description

[0001]This application claims the benefit of Korean Patent Application No. 2006-90661, filed Sep. 19, 2006, the contents of which are hereby incorporated herein by reference in their entirety.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]The present invention relates to an optical pointing device and a power supply semiconductor device therefor.[0004]2. Description of Related Art[0005]In general, an optical pointing device includes an optical unit, an image sensor, a motion value calculator, and an analog-to-digital (A / D) converter. Since a semiconductor device used for the optical pointing device is a system-on-chip (SOC), optimum operating voltages required for internal blocks are all different. Specifically, the operating voltage of the optical unit must be a threshold voltage or higher (here, the threshold voltage of a red light emitting diode (LED) is 2.7V, and the threshold voltage of a blue LED is 3.2V). The image sensor operates at a high voltage so that a ...

AI Technical Summary

Benefits of technology

The present invention provides an optical pointing device and a power supply semiconductor device that can adjust the power supply voltage based on the moving velocity of the device. This prevents excessive voltage from being applied to internal blocks that can operate at lower voltages, while still providing the necessary power for optimal performance. The optical pointing device includes an optical unit, motion sensor, and motion value calculator, while the power supply semiconductor device includes a power supply regulator and a serial voltage regulator. The power supply regulator can adjust the power supply voltage to the internal blocks of the device, while the serial voltage regulator can regulate the power supply voltage again to output the optimum power supply voltage for each block. This allows for a proper motion value to be obtained while still maintaining the necessary power for the other internal blocks. The power supply semiconductor device can also include a power supply voltage boost or drop to apply a variable optimum power supply voltage to each block. Overall, this invention provides a more efficient and effective power supply for an optical pointing device.

Problems solved by technology

As a result, some internal blocks, which may operate at the minimum voltage, receive an excessively high operating voltage to cause waste of power.

Therefore, an excessively high operating voltage applied to the CMOS logic circuit leads to a rise in current consumption, thus resulting in inefficiency and waste of power.

In this method, however, repeated use over a long period of the portable battery leads to a drop in an output voltage of the portable battery.

As a result, logic circuit design is subject to restrictions in power consumption.

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